Oil and gas wells are drilled into earth formations, first creating a borehole and then running and cementing casing in the borehole. Well tools such as bridge plugs, packers, cement retainers and frac plugs are often run into cased wells and set using setting tools powered by flammable power charges. Conventional well tools providing well casing sealing assemblies typically comprise a packer having one or more elastomeric sealing elements which are squeezed between a packer mandrel and the casing, and held in place by one more slip assemblies which are wedged between conical sleeves of the packers and the casing. The packers are configured for use as bridge plugs, tubing packers, cement retainers, and frac plugs.
Conventional packer setting tools have been used for setting packers, or well casing sealing assemblies. Conventional setting tools have power charge chambers in which flammable power charges are burned to generate pressurized gases which move one or more pistons to forcibly set the well tool being run within the well. One such setting tool is shown in U.S. Pat. No. 2,618,343 issued to Martin B. Conrad on Nov. 18, 1952. Conventional setting tools use hydraulic oil located between a first piston disposed in a first cylinder and a second piston disposed in a second cylinder. The first piston in the first cylinder is pushed directly by power charge gases and in turn pushes the hydraulic fluid, which then pushes the second piston in the second cylinder. The second piston is then typically connected by a rod and linkage to a setting sleeve for pushing against and setting the well tool in the casing.
The packer mandrels provide a central body on which various components are mounted. The mandrel is attached to a stationary portion of the setting tool and held in a fixed position, and the setting sleeve typically extends around the mandrel and is stroked downward against an uppermost sleeve of the well tool being set. The upper sleeve will then move downward toward a lower end of the mandrel, pushing anchor slips over conical elements and pressing an elastomeric seal element between the mandrel and the casing. During setting of the casing seal device, a shear pin will be sheared to release the setting tool from the set well tool so that the setting tool may be retrieved from the well and be redressed for repeated later use.